Tempo:
of the window so that any incidental water leakage through the window can be readily drained to the exterior.
Provide continuity of the water shedding surface at the first plane of protection by using sealant and trim at the window perimeter. A drip edge is recommended at the sill because it causes water to drip free of the cladding below, reducing the probability of water running back into the wall assembly and the staining created by concentrated water run-off.
Although insulating around the frame in the rough opening can provide some thermal benefit, it does limit the drainage capability. In areas of higher exposure, the use of sealant in the interior and an insulation material that can readily drain and dry is preferred. When exterior perimeter insulation is used, space should always be provided for drainage and drying between the insulation and the cladding.
Figure 131 shows two drip edge arrangements for a window sill. Attach windows securely to framing members (Figure 132).
131 Window sill 25 mm (1in.) extension beyond cladding or inner face of masonry sill 6% slope drip notch positioned 6 mm (1⁄4 in.) beyond cladding or 15 mm (5⁄8 in.) beyond inner face of masonry sill water-impermeable membrane over sloped subsill or over horizontal sill with dam
132 Window attachment rough opening dimensions 25 mm (1 in.) larger than outside of window frame to provide a minimum 12.5 mm (1⁄2 in.) space between the window frame and rough opening lintel fill space between window frame and rough opening from the inside with foam insulation or insulate and air-seal attach window with wood screws through sides of window frame only shims at jamb and sill junctions only shim at junction of multiple units jack stud cripple stud Note: Always refer to manufacturer's instructions.
Provide continuity of the water shedding surface at the first plane of protection by using sealant and trim at the window perimeter. A drip edge is recommended at the sill because it causes water to drip free of the cladding below, reducing the probability of water running back into the wall assembly and the staining created by concentrated water run-off.
Although insulating around the frame in the rough opening can provide some thermal benefit, it does limit the drainage capability. In areas of higher exposure, the use of sealant in the interior and an insulation material that can readily drain and dry is preferred. When exterior perimeter insulation is used, space should always be provided for drainage and drying between the insulation and the cladding.
Figure 131 shows two drip edge arrangements for a window sill. Attach windows securely to framing members (Figure 132).
131 Window sill 25 mm (1in.) extension beyond cladding or inner face of masonry sill 6% slope drip notch positioned 6 mm (1⁄4 in.) beyond cladding or 15 mm (5⁄8 in.) beyond inner face of masonry sill water-impermeable membrane over sloped subsill or over horizontal sill with dam
132 Window attachment rough opening dimensions 25 mm (1 in.) larger than outside of window frame to provide a minimum 12.5 mm (1⁄2 in.) space between the window frame and rough opening lintel fill space between window frame and rough opening from the inside with foam insulation or insulate and air-seal attach window with wood screws through sides of window frame only shims at jamb and sill junctions only shim at junction of multiple units jack stud cripple stud Note: Always refer to manufacturer's instructions.
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